1. Field of Invention
This invention relates generally to the field of geophysics and to seismic techniques for producing a representation of a section of the earth. In particular the invention relates to the field of processing methods for transforming original seismic traces to obtain transformed traces and for displaying such transformed traces.
2. Description of the Prior Art
Many of the signal processing methods that are applied to seismic trace data are linear operations, that is, linear transforms. Examples of such transforms are band pass filters, certain types of migration operations, and NMO. Some transform methods are expensive in computer usage terms.
3. Identification of Object of the Invention
A primary object of this invention is to provide a method which speeds up the processing of seismic trace data to obtain a transform function of such trace data.
The invention provides a method by which the computational time required to apply certain linear operations to seismic data traces can be decreased. The linear transform of a set of data traces can be approximated by the transformation of a smaller number of basis vectors followed by construction of the transform of the original data by simply scaling and summing the transformed basis vectors. For certain linear operations there is a computational savings in transforming the seismic data traces by this method. The linear transformation can be a cascaded set of separate linear operations combined to form the effect of a single linear operation. Examples of application of the method to actual seismic data show that the method works to reduce computation time.